Process of diffusion.



UNITED STATES PATENT OFFICE.

CARL STEFFEN, OF VIENNA, AUSTRIA-HUNGARY.

PROCESS OF DIFFUSION.

SPECIFICATION forming part of Letters Patent No. 718,030, dated January 6, 1903.

Application filed September 11, 1902. Serial No. 123,029. (No specimens.)

To all whom it may concern.-

Be it known that I, CARL STEFFEN, a subject of the Emperor of Austria-Hungary, residing at Vienna, Austria-Hungary, have in vented certain new and useful Improvements in Diffusion Processes, of which the following is a specification.

This invention relates to certain improvements in the process patented to me by United States Patent No. 674,483.

According to the diffusion process forming subject-matter of Patent No. 674,483 the integrating devices to form a homogeneous pulp, whereupon this pulp is being pressed,

out in suitable pressing devices and separated into a residue and the pressed juice. The sacchariferous pressed juice thus produced, with addition of a greater or smaller quantity of Water, is fed anew into'the diffusion apparatus of any known construction in order to serve there again for the partial diffusion of beet-root orsugar-cane slices and to be finally drawn off from the diffusion-battery in the shape of concentrated raw difiusion-ju'ice.

The improvements of Patent No. 674,483,

' forming the subject-matter of the present invention, consist in the following: It has been found that, first, if the extraction of sugarjuice from beet-root or sugar-cane slices according to Patent No. 674,483 is not continued upto the usual low limits, but isinterrupted at suitable higher percentage of sugar in the sugar-cane or beet-root, (about two per cent. of sugar;) second, if the diffusion liquid fed into the diifusion-battery at its end where slices are poor in sugar is applied at a temperature of from to 100 centigrade (preferably 80)-that is to say, at a temperature considerably higher than that used in the diffusion process; third, if the fresh beet-root or sugar-cane slices introduced at the end of the diffusion-battery or diffusion apparatus where the slices are rich in sugar are heated by means of heated raw diffusion-juice in any desired manner at a temperature of above 50 centigrade, (preferably 80.)

The object aimed at in Patent No. 674,483, consisting in a partial sugar extraction by means of diffusion, may be obtained in a very short period, (from about ten to fifteen minutes,) and if the well-known diffusion-battery is used for carrying. out the diffusion process some few battery vessels (about four or five) are sufficient to obtain the object viewed.

The whole diffusion period for the beet-root or sugar-cane slices taking but very short time (about ten to fifteen minutes) and the diffusion-battery consisting only of some few vessels, facility is thus alforded to apply the said high temperatures during the whole duration of the diffusion process without meet-:

ing with the drawbacks which invariably oc our in the practical execution of the old diffusion process when high temperatures are applied for the extraction of sugar from vegetable substances up to the lowest limits and when the use of diffusion-batteries with a great number of vessels cannot be avoided. These diificulties with the old process lie principally in the alteration of the structure of the vegetable substances under the action of high temperature during the dilfusion process lasting for a very long period. This alterationof the structure of the vegetables,

which, among others, shows itself in a considerable inflation of the elements of the plant which are capable of swelling'up, is the cause that the lixiviated slices can but insufficiently be pressed out.

In order to obtain with the process according to Patent No. 674,483 a better effect with the pressing operation, the partiallydiffused slices are disintegrated to form a pulp before the beginning of the pressing operation butif the period of the diffusion is reduced to the shortduration hereinbefore mentioned, and which is, according to Patent No. 674,483, sufficient for the purpose in View with the application and maintenance of high temperatures during the wholedifiusion process for a partial extraction of sugar from the vege- ICO oughly pressed out.

rendered possible to press out the partiallyexhausted hot slices immediately after they have left the difiusing apparatus by means of slice-presses of any construction or by means of roller-presses and to eliminate the same under the form of a residue poor in juice and containing a high proportion of dry substance (for beet-root about thirty-five per cent., for sugar-cane up to about fifty-five per cent.) and of small weight, (twenty-five per cent. of that of the beet-root,) while the expressed juice is correspondingly pure and exempt of fibers. Owing to this circumstance, the disintegration of the partially-diffused slices before pressing to form a pulp according to Patent No. 674,483 may be dispensed with, and the purpose aimed at in said patent is completely obtained under observation of the hereinbefore-mentioned measures by the direct pressing of the slices, partially diffused at high temperatures.

The execution of the process, similarly to that of Patent No. 674,483, is not limited to any determined construction of diffusing apparatus; but apparatuses of any well-known construction may be employed. The diffusion process is carried out in the usual manner in the diffusion-battery or other apparatus of a suitable construction; but according to Patent No. 674,483 the extraction operation by means of diffusion is inter-- rupted atahigher percentage of sugar in the treated slices, (about two per cent.,) whereupon the pressing operation is commenced. The pressed juices to be fed back into the diffusion-battery according to Patent No. 674,483, together with the additional water,

are heated to a temperature of between to 100 centigrade (preferably centigrade) before they are introduced into the diffusionbattery. The partially-diffused slices discharged from the diffusion-battery at their temperature of between 50 to centigrade, (preferably 80,) either with the surrounding diffusion-juice or previously separated from the same, are brought into well-known difiusion-slice presses of any construction or into roller-presses of wellknown construction and are separated into residua and pressed uice.

The fresh slices fed into the diffusion-battery may be heated in the well-known manner by means of heated raw diffusion-juice before the difiusion or during the same, or the heating may be effected according to the heating method described in its essence in Patent No. 674,483.

I claim The herein described diffusion process which consists in subjecting the sliced material to a difiusion action while in a heated condition; pressing the material; adding water to the diffusion liquid pressed from the material; heating the mixture thus obtained; supplying said heated mixture to the material before it is pressed; and drawing off concentrated diffusion liquid.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

CARL STEFFEN.

Witnesses:

AUGUST FUGGER, O. B. HURST. 

